Ecotopic expression of Ckb enhances TCR sensitivity and T cell response.

(A) Flow cytometric analysis of the activation marker CD25 on CD4 and CD8 T cells, cells were stimulated with plate-bound anti-TCR (10 µg/ml) and anti-CD28 (10 µg/ml) antibodies or left unstimulated for 16 h. (B) CFSE-labeled lymphocytes were stimulated with plate-bound anti-TCR (top 0.5 µg/ml, bottom 2 µg/ml) and anti-CD28 antibodies (top 0.5 µg/ml, bottom 2 µg/ml) or left unstimulated. Cells aliquots were analyzed for CFSE fluorescence as an indicator of cell division. Analyses were gated on CD4⁺ or CD8⁺ cells as indicated. (C) Analysis of cytokine expression. LN T cells were isolated from 6-week-old CkbTg and Littermate mice, left unstimulated or stimulated with PMA and IM for 4 h and then analyzed for CD4, CD8, IL-2 and IFN-γ expression. Values in the gating boxes indicate the percentage of IL-2⁺ or IFN-γ⁺ cells and numbers underneath the gating boxes indicate the MFI of IL-2 and IFN-γ. The results are representative of three independent experiments. Litt, littermate; CkbTg, Ckb transgenic mouse.